header{
    width: 100%;
    height: 2.3rem;
    overflow: hidden;
    position: relative;
    z-index: 99;
}
.w640 { width: 100%; margin-left: auto; margin-right: auto;}
@media only screen and (min-width: 640px) {
    .w640 { width: 640px; }
}
.title-list{
    width: 39rem;
    overflow: hidden;
    position: absolute;
    left:0;
    top: 0;
    -webkit-transform-style: preserve-3d;
}
.title-list li{
    float: left;
    padding: 0.5rem 0.8rem;
    font-size: 0.8rem;
    color: #bbb;
}
.title-list .on{
    color: #666;
    border-bottom: 3px solid #5cc2d7;
}
.video-box{
    padding: 0;
    border: 1px solid #fff;
    -webkit-box-sizing: border-box;
    -moz-box-sizing: border-box;
    box-sizing: border-box;
}
.class-img{
    width: 100%;
}
.class-title{
    width: 100%;
    text-align: center;
    font-size: .7rem;
}
.class-cover{
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, .3);
    position: absolute;
    left:0;
    top: 0;
}
.class-name{
    width: 100%;
    text-align: center;
    position: absolute;
    left:0;
    top: 50%;
    color: #ffffff;
    font-size: .75rem;
}
.video-list{
    width: 100%;
    height: 100%;
    border: 1px solid #f5f5f5;
    color: #999;

}
.video-list .imgBox{
    width: 100%;
}
.user-message{
    position: relative;
}
.header-page{
    width: 1.5rem;
    height: 1.5rem;
    border-radius: 50%;
    overflow: hidden;
    border: 3px solid #ffffff;
    box-sizing: content-box;
    position: absolute;
    left: .125rem;
    bottom: 0;
}
.header-page img{
    width: 100%;
}
.username{
    margin-left: 2.1rem;
    max-width: 50%;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    line-height: 1rem;
    font-size:.7rem;
}
.like{
    position: absolute;
    right: 0.2rem;
    top: 0;
    padding-left: .88rem;
    background: url("../img/heart2.png") no-repeat left center;
    -webkit-background-size: .8rem;
    background-size: .8rem;
    font-size:.7rem;
}
.describe{
    color: #333;
    padding:.2rem .2rem .4rem .4rem;
    margin: 0;
    font-size:.8rem;
    width: 100%;
    height: 2.5rem;
    text-overflow: ellipsis;
    display: -webkit-box;
    -webkit-box-orient: vertical;
    -webkit-line-clamp: 2;
    overflow: hidden;
}